Controller for a Multi-Phase Power Converter, Multi-Phase Power Converter and Method

Abstract

A controller ( 10 ) for controlling switching in a multiphase power converter ( 1 ) having a plurality of converter bridges ( 2 a, 2 b ), each associated with a phase. The controller ( 10 ) includes a driver block ( 10 a ) for generating gate driver signals for controlling power switches (HS 1 - 4, LS 1 - 4 ) in each of the converter bridges ( 2 a, 2 b ), an imbalance sensor block ( 10 b ) for identifying a power imbalance between the plurality of converter bridges ( 2 a, 2 b ), and an adjustment block ( 10 c ) for adjusting the control of the power switches (HS 1 - 4, LS 1 - 4 ) in response to the detection of a power imbalance by modifying timing of the generated gate driver signals.

1 . A controller for controlling switching in a multiphase power converter having a plurality of converter bridges, each associated with a phase, wherein the controller comprises:
 a driver block for generating gate driver signals for controlling power switches in each of the converter bridges;   an imbalance sensor block for identifying a power imbalance between the plurality of converter bridges; and   an adjustment block for adjusting the control of the power switches in response to the detection of a power imbalance.   
     
     
         2 . A controller according to  claim 1 , wherein the adjustment block is configured to adjust the phase delay between the phases of the plurality of converter bridges by controlling their respective power switches. 
     
     
         3 . A controller according to  claim 1 , wherein the adjustment block is configured to adjust the control of the power switches to modulate the effective time of the voltage gate driver signals. 
     
     
         4 . A controller according to  claim 3 , wherein the effective time is modulated in the order of hundreds of picoseconds up to hundreds of nanoseconds. 
     
     
         5 . A controller according to  claim 1 , wherein the driver block is configured to control the power switches in each of the converter bridges to have predetermined starting phase delay between their respective phases. 
     
     
         6 . A controller according to  claim 1 , wherein the adjustment block is configured to adjust the phase delay in the order of hundreds of picoseconds up to hundreds of nanoseconds. 
     
     
         7 . A controller according to  claim 1 , wherein the plurality of converter bridges comprises first and second converter bridges, wherein the driver block is configured to control the power switches in the first and second converter bridges to have a starting phase delay of 90 degrees, and
 wherein the adjustment block is configured to increase or decrease the starting phase delay based on the identified power imbalance.   
     
     
         8 . A controller according to  claim 1 , wherein the driver block generates gate driver signals for controlling the power switches in one of a half bridge and full-bridge topology for each of the plurality bridge converters. 
     
     
         9 . A controller according to  claim 1 , wherein the plurality of converter bridges are LLC bridges. 
     
     
         10 . A controller according to  claim 1 , wherein the imbalance sensor block identifies a power imbalance based on one or more of:
 a) identifying a difference between peak primary currents of the plurality of bridge converters;   b) identifying a difference between peak secondary currents of the plurality of bridge converters; and   c) identifying phase difference between a switching node voltage transition from high voltage to low voltage and a primary side current crossing a zero amp value.   
     
     
         11 . A multiphase power converter, comprising:
 a plurality of converter bridges, each associated with a phase; and   a controller according to  claim 1 .   
     
     
         12 . A multiphase power converter according to  claim 11 , wherein the plurality of converter bridges comprises first and second converter bridges, and
 wherein the driver block is for controlling the power switches in the first and second converter bridges to have a starting phase delay of 90 degrees, and the adjustment block is for increasing or decreasing the starting phase delay based on the identified power imbalance.   
     
     
         13 . A multiphase power converter according to  claim 11 or 12 , wherein the plurality of converter bridges comprise one of a half bridge and full-bridge topology. 
     
     
         14 . A multiphase power converter according to  claim 11 , further comprising a sensor arrangement connected to the imbalance sensor block, wherein the sensor arrangement is for sensing one or more of:
 a) a difference between peak primary currents of the plurality of bridge converters;   b) a difference between peak secondary currents of the plurality of bridge converters; and   c) a phase difference between a switching node voltage transition from high voltage to low voltage and a primary side current crossing a zero-amp value.   
     
     
         15 . A method for controlling switching in a multiphase power converter having a plurality of converter bridges, each associated with a phase, wherein the method comprises:
 generating gate driver signals for controlling power switches in each of the converter bridges;   identifying a power imbalance between the plurality of converter bridges; and   adjusting the control of the power switches in response to the detection of a power imbalance.